Lung Movement and Volume

Boyle’s Law

Pressure × volume = constant

Diffusion

Movement of energy from high to low concentration

Airway resistance

Pressure needed for air to travel, decreasing with radius and increasing with length

Compliance

Ability to stretch

Elasticity

Ability to unstretch

Passive breathing forces

Forces that push the breathing apparatus towards its resting state

Active breathing forces

Forces that push the breathing apparatus away from its resting state

Lung elastic recoil

Passive force pushing the breathing apparatus inward

Chest wall elastic recoil

Passive force pushing the breathing apparatus outward

Alveolar surface pressure

Passive force pulling alveoli in on themselves, disrupted by surfactants

Intrapleural pressure

Negative pressure coupling ribs to lungs

Transpulmonary pressure

Positive pressure keeping alveoli open (alveolar - intrapleural)

Inspiratory alveolar pressure

<0 cm H20

Resting alveolar pressure

0 cm H20

Expiratory alveolar pressure

>0 cm H20

Running speech alveolar pressure

5-10 cm H20

Steady utterance alveolar pressure

8 cm H20

Inspiratory reserve volume

Lung volume reached at forceful inhale (50%-100% range of total lung capacity)

Tidal volume

Lung volume during quiet resting breaths (40%-50% range of total lung capacity)

Expiratory reserve volume

Lung volume reached at forceful exhale (20%-40% range of total lung capacity)

Residual volume

Lung volume that keeps the alveoli open (0%-20% range of total lung capacity)

Inspiratory capacity

Inspiratory reserve volume and tidal volume

Functional residual capacity

Expiratory reserve volume and residual volume

Vital capacity

Inspiratory reserve volume, tidal volume, and expiratory reserve volume

Inspiratory reserve volume, tidal volume, and expiratory reserve volume

Forced expiratory volume

Measurement taken from the top half of a spirometry graph

Forced inspiratory volume

Measurement taken from the bottom half of a spirometry graph

Restrictive lung disease

Disease that reduces maximum flow and volume for the flow-volume loop and increases passive force of lungs

Obstructive lung disease

Disease that reduces maximum flow for the flow-volume loop and decreases passive force of lungs